Sealing means for wrappers



April 1936. A. G. s. LINDGREN 2,037,420

SEALING MEANS FOR WRAPPERS Filed May 10, 1935 finders 6 izrzg yrerz flrsaz, 07-76 y ill Patented Apr. 14, I 1936 PATENT OFFICE- SEALING MEANS FOR WRAPPERS .Anders Gustav Sebastian Lindgren, Goteborg, Sweden, assignor, by mesne assignments, to United States Envelope Company, Springfield,

Mass.

Application May 10,

1935, Serial No. 20,892

In..Sweden-Eebruai-y 24, 1934 1 Claim.

- Assealing means for envelopes, pay-bags and similar wrappers, it has been proposed to' apply to the sealing fi'ap or closure portion a coating of rubber solution or other adhesive, which, in its dried condition, has the property .of strongly sticking to a similar coating on a complementary area of the envelope, bag, or wrapper without first being moistened, which does not stick to uncoated parts. a

It has proven to be impractical to apply the adhesive at the very border orextreme edge of the sealing flap or closure portion of the envelope, bag, or wrapper, assuch articles when they are collected in stacks or bundles, or packed in boxes, are very apt to be stuck together at the extreme edges of their sealing flaps or closure portions by adhesive that even slightly. overruns said edges, in which case they cannot be separated without risk of being spoiled by peeling off of the adhesive coatings on their closure portions. according to my previous invention as set forth in United States Letters Patent No. 1,945,648, the adhesive on the flap or closure portion was made to terminate just short of the edge thereof,

making it possible in practice to use such drysealing means on envelopes, bags and similar wrappers.

The present invention has for its object to attain the same result as that of my previous invention, and at the same time to permit the adhesive coatings .on the flaps to be applied out to the very edges of the. flaps. Other and further objects of the invention will be made apparent by the following detailed description thereof, taken in connection with the accompanying'drawing, in which- Figs. 1, 2 and 3 are rear views of various kinds ofopen envelopes mpvided with sealing means, according to my invention.

Fig. 4 is an inside view of a wrapper or letter sheet provided with sealing means according to my invention, and I Fig. 5 is a perspective view of a stack or pack of envelopes of a form similar to Fig. 1,and illustrating the way in which sticking at the edges oi the flaps or closure portions is prevented.

Like reference characters refer to like parts in the different figures. V

In the envelopes shown by Figs. 1. and 2, the closure flaps, designated'in each instance by the numeral I, are provided with coatings 2 of the rubber solution, and similar coatings 3 are applied to complemental areas of each envelopes back wall. Likewise, in the envelope shown by Fig. 3, there are similar complemental coated Therefore the complemental coated areas into contact.

Thesame is true of the letter sheet or wrapper shown in Fig. 4 which, on its inner surface, has a border 4 of the dried rubber solution. All the,

area within said border can be used for writing or printing, and then, when the'sheet is folded on the line 5, .the border portions will adhere together, thus completely inclosing the written message.

In every case, the adhesive coating 2, 2' or 4 is carried out to the extreme edge of the flap or sheet, and notwithstanding this, it is possible, when such coatings have dried, to stack or pack the envelopes, bags, or wrappers in the manner shown in Fig. 5, with such extreme coated edges exactly in registry; this is made possible by the fact that, according to my invention, each such edge extremity, as soon as the coatings 2, 2' and 4 have dried, is sprinkled with talc, to provide a layer 6 of talc at such. outermost edge for the purpose of neutralizing the sticking properties of the coating at such edge.

I am aware that it has previously been proposed to cover an adhesive coating on a paste mark or stamp mark with tale in order to neutralize the sticking efiect when the marks are piled. However, in such cases the total area of coating has been covered with talc and thus has lost most of its adhesive property. Such a total covering is not intended here, where the stick.- ing effect is fully maintained on the flap.

What I claim is:

Sealing means for envelopes and the like, comprising a coating of dry-sealing adhesive on the closure portion of each envelope, anda similar coating on a complementary area of said.envelope, said coatings when dry adapted to stick mm; other but not to uncoated parts, the firstnamed coating extending to the extreme edge of the closure portion, and being overlaid at said extreme edge only with a talc-like substance, whereby when said articles are stacked or packed .with their said extreme edges in registry, they are prevented from sticking together at said extreme edges.

' ANDERS GUSTAV SEBASTIAN LINDGREN. 

